Glowlight Tetra care guide
Glowlight Tetra (Hemigrammus erythrozonus) — minimum tank 40 L, temperature 24-28 °C, pH 5.5-7.
Compiled by Aquairi from published sources · Published · Updated
Overview
The Glowlight Tetra (Hemigrammus erythrozonus) is a small characid native to the Essequibo basin in Guyana. It is recognised by a narrow, bright copper-red stripe extending from snout to tail base, producing a glowing effect under aquarium lighting.
Taxonomy
- Family: Characidae
- Genus: Hemigrammus
- Scientific name: Hemigrammus erythrozonus
Habitat
The species inhabits soft, slightly acidic blackwater tributaries of the Essequibo and Potaro river systems in Guyana, where waters are stained by tannins and shaded by overhanging vegetation.
Tank requirements
- Minimum tank volume: 40 L (10.6 US gal)
- Adult size: 3-4 cm
- Temperature: 24-28 °C (75-82 °F)
- pH: 5.5-7
- GH: 2-10 °dGH
- Water flow: low
- Lifespan: 3-5 years
- School size: ≥6 individuals
Diet
A micro-predator and omnivore consuming small invertebrates, insect larvae and plant debris. In captivity it accepts micro-pellets, fine flakes and small live or frozen foods such as daphnia, cyclops and baby brine shrimp.
Compatibility
A peaceful mid-water shoaling species. Maintain a group of at least six in a planted aquarium with subdued lighting. Suitable tankmates include other small characins, Corydoras, Otocinclus and dwarf rasboras. Avoid large or aggressive species.
Breeding
An egg-scatterer. Spawning is best induced in a separate tank with very soft, acidic water (pH 5.5-6.5, GH below 4), subdued lighting and fine-leaved plants or a spawning mop. Eggs hatch in about 24 hours; remove parents after spawning.
Conservation status
IUCN Red List: not formally assessed; populations appear stable and the species is extensively bred in captivity.
Breeding Glowlight Tetra
Overview
Hemigrammus erythrozonus is an egg-scattering characin that gives no parental care; the adults will eat the eggs and should be removed as soon as eggs are noticed. Wikipedia describes it as bred in captivity with a moderate level of difficulty, matching the intermediate rating.
Sexing
Mature females are more rounded in the belly than males and tend to grow a little larger; the slimmer males are more colorful. Differences become clear only as fish mature and females fill with eggs.
Breeding Setup
- Separate spawning tank, around 18 x 10 x 10 inches, dimly lit
- Fine-leaved plants (java moss) or spawning mops, or a mesh base so eggs fall out of reach
- Soft, acidic water: pH 5.5-6.5, GH 1-5 (Wikipedia gives 6-8 dGH at 26-28 C)
- Temperature 80-84 F (27-29 C); peat filtration and RO water are recommended, with a small air-powered sponge filter
Spawning Behavior & Trigger
Condition the breeders on small live foods. For pair spawning, condition the sexes separately and move the fattest female and best male to the spawning tank in the evening; they should spawn the following morning. During spawning the male shows rapid swimming and fin-locking and the pair often roll, sometimes turning upside down. Females release about 120-150 eggs.
Egg & Fry Care
Remove the adults at once, as they eat eggs. The eggs and early fry are light-sensitive, so keep the tank dark; Seriously Fish gives a hatch time of 24-36 hours and Wikipedia 20-25 hours, with fry free-swimming 3-4 days post-hatch. First foods are infusoria, then microworm or brine shrimp nauplii. Orange striping appears by about three weeks.
Common Challenges
Achieving suitably soft, acidic water and protecting the light-sensitive eggs and fry are the main hurdles. The first-feeding fry are small and need infusoria-grade foods before they can take brine shrimp nauplii.